Answer:
technical specialist
Step-by-step explanation:
Technical specialists are highly skilled and trained individuals that specialize in dealing with specific technical issues regarding machinery and/or software, e.g. they monitor and diagnose technical problems related to computers, either hardware or software related problems.
Technical specialists usually provide solutions to possible problems, and in this case Jefferson is part of a sales team and his role is to provide solutions that satisfy the customer's specific needs related to their construction business. He is in charge of showing customers how GRDR's tools can help them perform better, more efficiently or save money (hopefully all of them). Even though he is not responsible for closing the sale, if he cannot convince the client that GRDR's tools are good for them, then the sale wouldn't be made.